Corner cutting connects chiral colorimetry to net electric flux in lossless all-dielectric metasurfaces

TL;DR

This study demonstrates how corner cutting in nanostructures enables all-dielectric metasurfaces to distinguish circularly polarized light by linking shape-induced electric flux decoupling to colorimetric responses.

Contribution

It introduces a novel design method using corner cuts to control electric dipoles in dielectric nanoparticles for chiral light sensing.

Findings

Achieved far-field dichroism with L-shaped nanoparticles

Linked colorimetric response to near-field electric flux decoupling

Provided design guidelines for lossless chiral light sensors

Abstract

All-dielectric metasurfaces can produce structural colors, but the most advantageous design criteria are still being investigated. This work numerically studies how the two-dimensional shape of nanoparticles affects the colorimetric response under circularly polarized light (CPL) to develop a sensor distinguishing CPL orientations. Using lossless dielectric materials (silicon nitride on silicon dioxide), we achieve far-field dichroism by modifying oblong nanoparticles into L-shaped structures through corner cuts. This design suppresses one electric dipole under CPL illumination, leading to differential colorimetric responses. We link these responses to a decoupling effect in the near-field net electric flux. Our findings provide design guidelines for all-dielectric, lossless colorimetric sensors of chiral light.